This invention relates generally to flush cleaning of surfaces in which a sheet of water or other fluid is released suddenly to clean a surface such as the floor of a livestock confinement facility. The basic principles of such flush cleaning are discussed in U.S. Pat. No. 3,223,070. It has been found that such flush cleaning works best if the water is released at a pressure in the range of 20- to 50-feet of water column, and if such release is effected through distributed outlets. Accordingly, an elevated water tank or other source of pressurized water is typically connected to various distributed outlets by piping in the range of 12-inches in diameter. Furthermore, in large facilities it is preferable that each outlet be operable independent of all others. Thus, each such outlet is equipped with a valve that is capable of opening the outlet in a rapid fashion, as well as sealing the outlet while the water is gushing from the outlet under the pressures discussed above. Such valves are what are referred to generally herein as flush valves, and are the focus of the present invention.
Some conventional valves might function effectively as flush valves, but are often quite expensive. Furthermore, conventional valves usually provide at least some degree of controllability of the flow rate of the liquid flowing through the valve, controllability that is not necessary for flush valve applications. Accordingly, conventional valves are significantly over-capable for flush valve applications.
Known flush valves include a flat pipe opening that is sealed by a seal plate pressed against the opening from outside the pipe. A simple automatic actuator for such a flush valve includes an air pillow fixed relative to the pipe opening, with the seal plate located between the air pillow and the pipe opening. Inflating the air pillow closes the valve and deflating the air pillow allows the pressure of the water to force the valve open. The plate is held in alignment with the pipe opening by one or more pedestals that slidably interfit with the pipe opening. Furthermore, the pedestals hold the seal plate in a fixed axial alignment with the pipe opening so that the air pillow pushes evenly on the seal plate.
These known flush valves have several drawbacks, including the requirements of a source of compressed air, an interconnection from such a source to the various valves, and the addition of controls at each valve to control the air. Furthermore, such known flush valves are in essence omnidirectional, and do not divert the flow of water exiting the pipe opening in any particular direction.
Flush systems of the type for which the present invention is designed use quantities of water that are sufficiently high to justify recycling the water. Furthermore, they are used in environments in which the water quickly becomes saturated with rather harsh impurities such as cow manure, sand, gravel and other particulates. Accordingly, the recycled water is particularly destructive of mechanical devices such as valves. This leads to a rapid deterioration of the valves, such that any valves requiring precision alignment of parts quickly become non-functional.